Chapter 4
105
HP BIOS
BIOS Addresses
HP I/O Port Map (I/O Addresses Used by the System
1
)
Peripheral devices, accessory devices and system controllers are accessed via the system
I/O space, which is not located in system memory space. The 64 KB of addressable I/O
space comprises 8-bit and 16-bit registers (called I/O ports) located in the various system
components. When installing an accessory board, ensure that the I/O address space
selected is in the free area of the space reserved for accessory boards (100h to 3FFh).
1. If configured.
Table 4-4. HP I/O Port Map
Default Values for
I/O Address Ports
Function
0000 - 000F
DMA controller 1
0020 - 0021
Master interrupt controller (8259)
002E - 002F
NS-317 Configuration registers
0040 - 0043
Timer 1
0060, 0064
Keyboard controller (reset, slow A20)
0061
Port B (speaker, NMI status and control)
0070
Bit 7: NMI mask register
0070 - 0071
RTC and CMOS data
0080
Manufacturing port (POST card)
0081 - 0083, 008F
DMA low page register
0092
PS/2 reset and Fast A20
00A0 - 00A1
Slave interrupt controller
00C0 - 00DF
DMA controller 2
00F0 - 00FF
Co-processor error
0130 - 013F
AD1816 sound system
0170 - 0177
Free (IDE secondary channel)
01F0 - 01F7
IDE primary channel
0200 - 0207
AD1816 Joystick port
0220 - 0232
AD1816 Soundblaster
0278 - 027F
LPT 2
02E8 - 02EF
Serial port 4 (COM4)
02F8 - 02FF
Serial port 2 (COM2)
0372 - 0377
Free (IDE secondary channel, secondary flexible disk drive)
0378 - 037A
LPT1
0330 - 038B
AD1816 Ad-lib (FM)
03B0 - 03DF
VGA
03E8 - 03EF
COM3
03F0 - 03F5
Flexible disk drive controller
03F6
IDE primary channel
03F7
Flexible disk drive controller
03F8 - 03FF
COM1
04D0 - 04D1
Interrupt edge/level control
0678 - 067B
LPT2 ECP
Summary of Contents for X Class 500/550MHz
Page 6: ...6 Contents ...
Page 8: ...8 Figures ...
Page 15: ...15 1 System Overview ...
Page 66: ...66 Chapter2 System Board Devices on the ISA Bus ...
Page 96: ...96 Chapter3 Interface Boards and Mass Storage Drivers Connectors and Sockets ...
Page 134: ...134 Chapter5 Tests and Error Messages Beep Codes ...
Page 135: ...135 A Regulatory Information and Warranty ...
Page 146: ...146 AppendixA Regulatory Information and Warranty HP Hardware Warranty ...